Grab.



D. J, BARNARD.

GRAB.

APPLICATION FILED APR. 26. 1915.

1,192,490. Patented July 25,1916.

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GRAB.

APPLICATION men APR. 25, 1915.

Patented July 25, 1916.

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DUDLEY JAMES TBARNARD, OF EAST HAM, ENG LAND.

GRAB.

Specification of Letters Patent.

Patented July 25, 1916.

Application filed April 26, 1915. Serial No. 23,985.

To all whom it may concern Be it known that I, DUDLEY JAMES BAR- NARD, a subject of IIis Majesty the King of Great Britain, and a resident of East Ham, in the county of Essex, England, have invented a certain new and useful Improvement in Grabs, of which the following is a specification.

The present invention relates to grabs and will be described with particular reference to grabs of the type in which a single chain or rope serves for hoisting purposes and also for opening and closing the buckets and in which the bucket sections are pivoted on two separate pivots carried by a combined beam and casing, the hinge portions of the bucket sections being provlded with interengaging means to prevent any tendency of the parts to overbalance, though it will be obvious that the invention is not limited in its application to grabs having these particular features.

The object of this invention is to provide improved means for checking or retarding the opening action of the bucket sections as the two sections open to discharge the contents of the bucket.

According to this invention the grab is provided with a dash pot adapted to be actuated by the turning movement of the pivot on which one of the bucket sections is mounted.

In the accompanying drawing the invention is illustrated as applied to a grab of the single chain type, actuated in the manner described in the specification of my application for Letters Patent, Serial No. 695069, filed May 1, 1912, merely by way of example, as the invention forming the subject of this application may be applied to different forms of grabs.

Figure 1 is a side elevation of one embodiment of the invention, showing the buckets in open position. Fig. 2 is a similar view showing the buckets in closed position. i Fig. 3 is a plan of part of one end of the grab as shown in Fig. 1, and Fig. 1 is a similar view with parts of the mechanism removed.

In the example of construction illustrated, 1 and 2 indicate the two bucket sections: 3 the combined beam and easing, l the chain wheel or drum loosely mounted on a shaft 4. 5 the four supporting arms, 6 the bucket closing chain (one on either side of the grab) and 7 the drum upon which such chain is wound. means, not illustrated of the form described and illustrated in my aforesaid prior specification, being provided for connecting the shaft 1 with the drum t while the buckets are being closed. The hauling rope 36 is provided, as in my aforesaid application, with a stop 36* so that when a predetermined length of rope has been unwound from the drum 1 and the bucket closing chains are fully unwound, the stop 36* will come into contact with the cross bar and thus support the grab.

The bucket sections 1, 2, are pivoted on plns 8, 9, respectively which pass through bosses formed on the beam or casing 3, and are secured in position by split pins 10 (Fig. 4). In the construction illustrated the bucket sections are caused to co-act with each other by means of toothed segments 11, 12, formed in one with or riveted to said sections, the extent of the opening movement being limited by the fiat faces 13, 14, on the sections 1, 2, coming into contact with each other.

For the purpose of checking the opening of the bucket sections and preventing the faces 13, 14, coming together with a shock a dash pot 15 filled with oil is provided, such dash pot being mounted on one side of the grab in the following manner: Referring to Fig. 4: it will be seen that the end of the beam 3 is provided with two bosses 16, 17 through which the pins 8 and 9 pass. The pin 9 fits closely in the boss 17, but the pin 8, being squared, necessarily passes somewhat freely through the boss 16, this however is not material as the pin is supported at one end in the plate 18 and at the other end in thebeam 3. The boss 16 is provided with an upwardly projecting lug 19 adapted to be embraced by the lugs 20 provided on the closed end of the cylinder 15, and to be secured thereto by a pin 21. Two links 22, 23, are pivoted on the outer end 2% of the pistonrod, the other ends of such links being pivotally connected to two clutch members 25, 26, mounted on the square part of the pin 8, so that they have no independent rotary movement thereon apart from the bucket section. The clutch member 25 is located between the end of the boss 16 and the inner face of the toothed segment 11, and the clutch member 26 is located in the recess 27 provided in the boss 16. The cylinder 15 is provided near the closed end with an air valve 28 and near its other end with a plug 29 through which the cylinder is filled.

It will be seen from Fig. 2, that when the grab is closed the piston of the dash pot is in its innermost position the cylinder being in a horizontal position, the clutch members occupying a position approximately at to a line drawn through the pivot pins 8 and 9, When the grab is opened however, the pin 8 rotates with the bucket section 1 and rotates the clutch members 25, 26, approximately through an angle of 90, that is into a position approximately at &5 to a line drawn through the pivot pins 8 and 9 but on the right of a vertical line drawn through the pivot pin 8, the piston being drawn outwardly, the cylinder remaining in a horizontal position.

WVhile the invention has been described and illustrated with reference to my afore said specification it will be understood that the invention is not limited in any. manner thereby, as it may be applied to difi erent forms of grabs whether of the single or 'multiple chain type.

IVhat I claim 1s:

1. In a grab, the bucket sections of which are mounted on pivot pins carried by a beam, the combination of means to check or retard the opening action of such sections, said means being partly carried by the beam and partly by one of said pins, such pin being actuated by the rotative movement of the bucket sections during the opening and closing movements.

'2. In a grab, the bucket sections of which are pivotally mounted on independent pivot pins carried by a beam, the combination of a dash pot actuated by the rotative movement of the bucket sections to check or retard the opening action of such sections,

the beam and part by one of thepivot pins vwhich is arranged to turn in the beam and with the bucket sections.

3. In a grab, the bucket sections of which are mounted on a beam, the combination of means actuated by the rotative action of the bucket sections to check or retard the opening action of such sections, comprising a boss formed on the beam, a lug formed on said boss, a pivot pin located in said boss, a squared portion formed on said pivot pin, clutch members mounted on said squared portion, a dash pot cylinder pivotally connected to said lug, a piston rod in said cylinder and links connecting said piston rod with said clutch members.

4. In a grab of the kind herein described the bucket sections of which are pivoted on a beam the combination of means actuated by the rotative action of the bucket sections to check or retard the opening action of such sections, comprising bosses formed on the ends of said beam, independentpivot pins for each of said bucket sections rotatively mounted in said bosses, a lug formed on one of said bosses a squared portion formed on the pivot pin mounted in said boss, clutch members mounted on said squared portion, a dash pot cylinder pivotally connected to the lug on said boss, a piston rod in said cylinder and links connecting said piston rod with said clutch members.

In testimony whereof I have hereunto set my hand.

'DUDLEY JAMES BARNARD.

IVitnesses H. D. JAMnsoN, O. J. WVORTH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

